Fig 2: Expression of GPR87 in GPR87-expressing human bladder cancer cells RT112 after infection with adenoviral vectors. (A) Time-dependent and dose-dependent GPR87 gene expressions in RT112 cell; (B) Time-dependent GPR87 protein expressions in RT112 cells. MOI: multiplicity of infection; * p < 0.05; ** p < 0.005, vs. Ad-scramble treatment.

Fig 3: Clinical Relevance of GPR87-Induced Activation of STAT3 in Human PDA(A) The expression levels of p-STAT3 and p-JAK2 were associated with the expression of GPR87 in 121 primary human PDA specimens. Two representative cases are presented. (B) Percentage of samples showing low or high p-STAT3 (Tyr705) or p-JAK2 (Tyr1007-1008) expression in 121 primary human PDA specimens relative to the levels of GPR87. (C and D) Western blot (C) and correlation analyses (D) of GPR87 expression with the levels of p-STAT3, p-JAK2, and STAT3 transcriptional activity in eight freshly collected human PDA samples. β-Actin served as loading control. E) The schematic diagram of GPR87 regulating the expasion of PDA stem cells.

Fig 4: GPR87 Promotes the Expansion of PDA Stem Cells In Vitro(A) Representative images showing sphere formation ability after GPR87 overexpression or knockdown. (B) Sphere formation assay for GPR87 overexpression of knockdown after three consecutive passages. (C) Sphere formation assay for the fold change in the number of cells per sphere after GPR87 overexpression or knockdown. (D) SP population assay showing that overexpressing GPR87 promoted the SP cells, whereas silencing of GPR87 attenuated the SP cells in the indicated cells. (E) qPCR analysis of the expression of PDA stem cell markers, including CD133, EpCAM, CD24, CD44, and MET, in the indicated cells. Error bars represent the means ± SD of three independent experiments. *p < 0.05.

Fig 5: Cell viability evaluated by MTT assay in six GPR87-expressing bladder cancer cells. Ad-shGPR87 inhibited the proliferation of bladder cancer cells with the wild-type p53 (A–D), but not the cells with mutant p53 (E,F). Cells were infected with Ad-shGPR87 at a MOI of 20. Each cell viability assay was performed in triplicate and repeated three times. The cell viability of the treatment group was normalized with the value from the PBS treatment group and was shown as mean values ± SD. A comparison between Ad-shGPR87 and Ad-scramble group was carried out with the independent Student’s t-test on each individual day. MOI: multiplicity of infection; * p < 0.05; ** p < 0.005, vs. Ad-scramble treatment.